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<title>Codeforces</title>

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Codeforces

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</style><table class="infobox vcard"><caption class="infobox-title fn org">Codeforces</caption><tbody><tr><td colspan="2" class="infobox-image"></td></tr><tr><th scope="row" class="infobox-label"><div style="display: inline-block; line-height: 1.2em; padding: .1em 0;">Type of site</div></th><td class="infobox-data"><a href="Competitive_programming" title="Competitive programming">Competitive programming</a></td></tr><tr><th scope="row" class="infobox-label">Available in</th><td class="infobox-data">English, Russian</td></tr><tr><th scope="row" class="infobox-label">Country of origin</th><td class="infobox-data"><a href="Russia" title="Russia">Russia</a></td></tr><tr><th scope="row" class="infobox-label">Owner</th><td class="infobox-data">Mikhail Mirzayanov</td></tr><tr><th scope="row" class="infobox-label">Created by</th><td class="infobox-data">Mikhail Mirzayanov</td></tr><tr><th scope="row" class="infobox-label">URL</th><td class="infobox-data url"><a rel="nofollow" class="external text" href="https://codeforces.com/">codeforces.com</a></td></tr><tr><th scope="row" class="infobox-label"><a href="Registered_user" title="Registered user">Users</a></th><td class="infobox-data">1,692,402</td></tr><tr><th scope="row" class="infobox-label">Launched</th><td class="infobox-data">April 10, 2009 (2009-04-10)</td></tr><tr><th scope="row" class="infobox-label">Current status</th><td class="infobox-data category">Active</td></tr></tbody></table>

Codeforces (<a href="Russian_language" title="Russian language">Russian</a>: Коудфорсес) is a website that hosts <a href="Competitive_programming" title="Competitive programming">competitive programming</a> contests.<a href="#cite_note-1">[1]</a> It is maintained by a group of competitive programmers from <a href="ITMO_University" title="ITMO University">ITMO University</a> led by Mikhail Mirzayanov.<a href="#cite_note-news_itmo-2">[2]</a> Since 2013, Codeforces claims to surpass <a href="TopCoder" class="mw-redirect" title="TopCoder">TopCoder</a> in terms of active contestants.<a href="#cite_note-3">[3]</a> As of 2019, it has over 600,000 registered users.<a href="#cite_note-4">[4]</a> On its 15th anniversary, Codeforces had a total of 1,692,402 users with at least one submission.<a href="#cite_note-5">[5]</a> Codeforces along with other similar websites are used by some sport programmers, like <a href="Gennady_Korotkevich" title="Gennady Korotkevich">Gennady Korotkevich</a>, <a href="Petr_Mitrichev" title="Petr Mitrichev">Petr Mitrichev</a>, Benjamin Qi and <a href="Makoto_Soejima" title="Makoto Soejima">Makoto Soejima</a>, and by other programmers interested in furthering their careers.<a href="#cite_note-6">[6]</a><a href="#cite_note-7">[7]</a><a href="#cite_note-8">[8]</a>

<div class="mw-heading mw-heading2"><h2 id="Overview">Overview</h2></div>

Codeforces is a platform where people generally practice competitive programming<a href="#cite_note-9">[9]</a><a href="#cite_note-10">[10]</a><a href="#cite_note-11">[11]</a><a href="#cite_note-12">[12]</a> and it offers the following features:

<ul><li>Short (2-hours) contests, called "Codeforces Rounds", held about once a week<a href="#cite_note-13">[13]</a><a href="#cite_note-14">[14]</a></li>

<li>Educational contests (2-2.5 hours, with 12 hours (24 hours before Round 45) hacking period),<a href="#cite_note-15">[15]</a> held 2-3 times per month;</li>

<li>Challenge/hack other contestants' solutions;</li>

<li>Solve problems from previous contests for training purposes;</li>

<li>"Polygon" feature for creating and testing problems;</li>

<li>Social networking through internal public blogs.</li></ul>

<div class="mw-heading mw-heading2"><h2 id="Rating_system">Rating system</h2></div>

Contestants are rated by a system similar to <a href="Elo_rating_system" title="Elo rating system">Elo rating system</a>. There are usually no prizes for winners, though several times a year special contests are held, in which top-performing contestants receive T-shirts. Some bigger contests are hosted on Codeforces base, among them "The Lyft Level 5 Challenge 2018", provided by <a href="Lyft" title="Lyft">Lyft</a><a href="#cite_note-16">[16]</a> or "Microsoft <a href="Q_Sharp" title="Q Sharp">Q#</a> Coding Contest — Summer 2018" provided by <a href="Microsoft" title="Microsoft">Microsoft</a>.<a href="#cite_note-17">[17]</a>

Contestants are divided into ranks based on their ratings. Since May 2018, users with ratings between 1900 and 2099 can be rated in both Div. 1 and Div. 2 contests. At the same time, Div. 3 was created for users rated below 1600. There is also a Div. 4, which is for users rated below 1400.<a href="#cite_note-18">[18]</a>

<th>Rating range

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<th>Title

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<th>Division

</th></tr>

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<td>≥ 4000

</td>

<td>eponym

</td>

<td>1

</td></tr>

<tr>

<td>3000 — 3999

</td>

<td>Legendary Grandmaster

</td>

<td>1

</td></tr>

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<td>2600 — 2999

</td>

<td>International Grandmaster

</td>

<td>1

</td></tr>

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<td>2400 — 2599

</td>

<td>Grandmaster

</td>

<td>1

</td></tr>

<tr>

<td>2300 — 2399

</td>

<td>International Master

</td>

<td>1

</td></tr>

<tr>

<td>2100 — 2299

</td>

<td>Master

</td>

<td>1

</td></tr>

<tr>

<td>1900 — 2099

</td>

<td>Candidate Master

</td>

<td>1/2

</td></tr>

<tr>

<td>1600 — 1899

</td>

<td>Expert

</td>

<td>2

</td></tr>

<tr>

<td>1400 — 1599

</td>

<td>Specialist

</td>

<td>2/3

</td></tr>

<tr>

<td>1200 — 1399

</td>

<td>Pupil

</td>

<td>2/3/4

</td></tr>

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<td>≤ 1199

</td>

<td>Newbie

</td>

<td>2/3/4

</td></tr></tbody></table>

<div class="mw-heading mw-heading2"><h2 id="History">History</h2></div>

Codeforces was created by a group of competitive programmers from <a href="Saratov_State_University" title="Saratov State University">Saratov State University</a> led by Mike Mirzayanov. It was originally created for those interested in solving tasks and taking part in competitions.<a href="#cite_note-news_itmo-2">[2]</a> The first Codeforces Round was held on February 19, 2010 with 175 participants. As of the end of August 2022, over 800 rounds were held, with over 9000 registered competitors per round on average. Before 2012, Codeforces Rounds were titled "Codeforces Beta Rounds" to indicate that the system was still under development.

<div class="mw-heading mw-heading2"><h2 id="Academic_use">Academic use</h2></div>

Codeforces is recommended by many universities.<a href="#cite_note-19">[19]</a><a href="#cite_note-20">[20]</a> According to <a href="Daniel_Sleator" title="Daniel Sleator">Daniel Sleator</a>, professor of <a href="Computer_Science" class="mw-redirect" title="Computer Science">Computer Science</a> at <a href="Carnegie_Mellon_University" title="Carnegie Mellon University">Carnegie Mellon University</a>, competitive programming is valuable in computer science education, because competitors learn to adapt classic algorithms to new problems, thereby improving their understanding of algorithmic concepts. He has used Codeforces problems in his class, 15-295: Competition Programming and Problem Solving.<a href="#cite_note-21">[21]</a> At the <a href="National_University_of_Singapore" title="National University of Singapore">National University of Singapore</a>, Codeforces rating is also used as an entrance qualifying criterion for registering for a 4-unit course, CS3233 Competitive Programming, as students have to achieve a rating of at least 1559 to be able to register for the course.<a href="#cite_note-22">[22]</a>

<ul><li><a href="CodeChef" title="CodeChef">CodeChef</a></li>

<li><a href="CodeFights" class="mw-redirect" title="CodeFights">CodeFights</a></li>

<li><a href="Facebook_Hacker_Cup" class="mw-redirect" title="Facebook Hacker Cup">Facebook Hacker Cup</a></li>

<li><a href="Google_Code_Jam" title="Google Code Jam">Google Code Jam</a></li>

<li><a href="HackerRank" title="HackerRank">HackerRank</a></li>

<li><a href="International_Collegiate_Programming_Contest" title="International Collegiate Programming Contest">International Collegiate Programming Contest</a></li>

<li><a href="Online_judge" class="mw-redirect" title="Online judge">Online judge</a></li>

<li><a href="Topcoder" title="Topcoder">Topcoder</a></li>

<li><a href="UVa_Online_Judge" title="UVa Online Judge">UVa Online Judge</a></li>

<li><a href="LeetCode" title="LeetCode">LeetCode</a></li>

<li><a href="Competitive_programming" title="Competitive programming">Competitive programming</a></li>

</ul>

<div class="mw-heading mw-heading2"><h2 id="References">References</h2></div>

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</style><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20201109024608/https://www.mic.com/articles/186412/north-korean-college-coders-beat-stanford-university-in-a-2016-competition-heres-why-that-matters#.9baJjoyF5">"North korean college coders beat Stanford University in a 2016"</a>. mic.com. Archived from <a rel="nofollow" class="external text" href="https://mic.com/articles/186412/north-korean-college-coders-beat-stanford-university-in-a-2016-competition-heres-why-that-matters#.9baJjoyF5">the original</a> on November 9, 2020. <q>Codeforces — a Russian competitive coding site with contestants from around the world</q></cite>

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<div class="mw-heading mw-heading2"><h2 id="External_sources">External sources</h2></div>

<ul><li><a rel="nofollow" class="external text" href="https://codeforces.com/">Official website</a></li></ul></div><div><div class="zim-footer">

This article is issued from <a class="external text" title="Last edited on 2025-06-01" href="https://en.wikipedia.org/wiki/?title=Codeforces&oldid=1293322083">Wikipedia</a>. The text is available under <a class="external text" href="https://creativecommons.org/licenses/by-sa/4.0/deed.en">Creative Commons Attribution-Share Alike 4.0</a> unless otherwise noted. Additional terms may apply for the media files.

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